title: Radiosterilization of rat liver microsome containing postmitochondrial supernatant for mutation assays.
abstract: Gamma-irradiation was effectively employed to sterilize rat liver postmitochondrial supernatant (PMS), which is required for the metabolic activation of soots and soot-derived polycyclic aromatic hydrocarbons to mutagens. When a known number of Bacillus subtilis spores were added to the PMS and gamma-irradiated at -80 degrees C, a 2-Mrad dose resulted in a 7.5 log kill of the spores. A dose of 3 Mrads was selected as a sufficient effective sterilizing dose and had no significant effect upon the ability of gamma-irradiated PMS to metabolically activate diesel soot and two diesel soot components, benzo(a)pyrene and fluoranthene to mutagens in a Salmonella typhimurium 8-azaguanine resistance forward mutation assay. Three Mrads of gamma-irradiation also had no effect upon the ability of PMS to activate benzo[a]pyrene to a mutagen for the human lymphoblasts. However, gamma-irradiation did reduce the ability of PMS to activate dimethylnitrosamine to a mutagen for S typhimurium.
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000528:radiation effects; D001711:Biotransformation / Q000528:radiation effects; D002478:Cells, Cultured; D005720:Gamma Rays; D006801:Humans; D066298:In Vitro Techniques; D008862:Microsomes, Liver / Q000528:radiation effects*; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens / Q000378:metabolism; D051381:Rats; D013242:Sterilization / Q000379:methods*; D013347:Subcellular Fractions / Q000528:radiation effects
chemical_list: D009153:Mutagens